Hi Hapaphoto,
welcome to te Apple (user-to-user) Community!
Re: "How to unpin timers on apple watch. Not even edit works"
Am no expert in this area, yet your question deserves some response.
Seems in WatchOS 11 there are now 8 fixed timers (at the top) that can not be edited or deleted.
The custom timers, if any, that you can add below them can be edited, or deleted as you decide.
(You may have already read the details in Apple Support's article: Set timers on Apple Watch - Apple Support)
if something is not working as expected, if you haven't already, you could try restarting your watch:
How to: Restart Apple Watch - Apple Support
There's a short third-party (Non-Apple) video online that shows how to remove pinned timers:
https://www.youtube.com/watch?v=vsrIUqm0MFE
Apple Watch Support Team have a website (info. / support / contact) online:
Apple Watch - Official Apple Support
If you are uncomfortable about accepting the recent change, you may want to send feedback to Apple: They will likely not reply, yet your feedback will reach those who can make changes, if others are also requesting them.
Web-form for feedback: Feedback - Watch - Apple
All the best :-)